package com.notary.util;

import com.itextpdf.text.pdf.PdfReader;
import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.rendering.PDFRenderer;

import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;

public class pdf2ImageDemo {
    public static void main(String[] args) {
        String outPutPath = "D:\\test.pdf";
        String dstImgFolder = "D:\\images";
        long start = System.currentTimeMillis();
        pdf2ImageDemo(outPutPath, dstImgFolder, 96);
        long end = System.currentTimeMillis();
        System.out.println("总共耗时：" + (end - start));
    }

    /***
     * PDF文件转PNG/JPEG图片
     * @param PdfFilePathpdf完整路径
     * @param imgFilePath图片存放的文件夹
     * @param dpi越大转换后越清晰，相对转换速度越慢,一般电脑默认96dpi
     */
    public static void pdf2ImageDemo(String PdfFilePath, String dstImgFolder, int dpi) {
        File file = new File(PdfFilePath);
        PDDocument pdDocument;
        try {
            String imgPDFPath = file.getParent();
            int dot = file.getName().lastIndexOf('.');
            // 获取图片文件名
            String imagePDFName = file.getName().substring(0, dot);
            String imgFolderPath = null;
            if (dstImgFolder.equals("")) {
                // 获取图片存放的文件夹路径
                imgFolderPath = imgPDFPath + File.separator + imagePDFName;
            } else {
                imgFolderPath = dstImgFolder + File.separator + imagePDFName;
            }

            if (createDirectory(imgFolderPath)) {
                pdDocument = PDDocument.load(file);
                PDFRenderer renderer = new PDFRenderer(pdDocument);
                PdfReader reader = new PdfReader(PdfFilePath);
                int pages = reader.getNumberOfPages();// 获取PDF页数
                System.out.println("PDF page number is:" + pages);
                StringBuffer imgFilePath = null;
                for (int i = 0; i < pages; i++) {
                    String imgFilePathPrefix = imgFolderPath + File.separator + imagePDFName;
                    imgFilePath = new StringBuffer();
                    imgFilePath.append(imgFilePathPrefix);
                    imgFilePath.append("_");
                    imgFilePath.append(String.valueOf(i + 1));
                    imgFilePath.append(".png");// PNG
                    File dstFile = new File(imgFilePath.toString());
                    BufferedImage image = renderer.renderImageWithDPI(i, dpi);
                    ImageIO.write(image, "png", dstFile);// PNG
                }
                System.out.println("PDF文档转PNG图片成功！");
            } else {
                System.out.println("PDF文档转PNG图片失败：" + "创建" + imgFolderPath + "失败");
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    private static boolean createDirectory(String folder) {
        File dir = new File(folder);
        if (dir.exists()) {
            return true;
        } else {
            return dir.mkdirs();
        }
    }

}
